Re: kvm errors with 4.9.0-9 kernel.

[Étienne Mollier <etienne.mollier@mailoo.org>]

John J. Rushford, on 2019-05-19:
> Greetings,

Good Day John,

This:

> kernel: [    6.234764] kvm_intel: Unknown symbol cpu_tlbstate (err -22)
> kernel: [    6.235463] kvm_intel: Unknown symbol mds_user_clear (err 0)
> kernel: [    6.330732] kvm_intel: disagrees about version of symbol cpu_tlbstate

seems most likely related to that security upgrade:

        https://www.debian.org/security/2019/dsa-4444

I don't an adequate machine readily available at hand to confirm
this behaviour of KVM using Debian Stretch native kernel today,
I will let others answer on that.  Search engines are quite dry
about it.  What I can say is that did not appear on newer
upstream kernels running with updated microcodes.

Out of curiosity, do you happen to have the non-free package
"intel-microcode" installed on your machine, and if so, is it up
to date?  Note that if you want to try it, you will have to
reboot you machine for allowing the kernel to apply the newer
microcode version to the CPU.

If your machine is up to date, then it would seem that the KVM
implementation of Debian native kernel does not take into
account changes made necessary by the newer security update.  In
which case, you can report a bug against the linux-image package
that is installed on your system.

Kind Regards,
-- 
Étienne Mollier <etienne.mollier@mailoo.org>